Roll-up doors and curtains are commonly used in various applications such as to isolate the inside of a building from the outside, separate two rooms within a structure, or prevent the contents or environment of a room from escaping from the room such as in the case of a walk-in freezer. Another use involves large removable partitions positioned so as to isolate one portion of a room such as where an item is being spray painted or cleaned using a high power water jet from other portions of the room. In these applications, the roll-up door or curtain, which hereinafter is referred to as a partition for simplicity, is mounted to an overhead cylinder which is typically rotated by an electric motor for unrolling the partition to an extended position or retracting the partition by winding it onto the tube. Opposed lower ends of the partition are connected to moving cables or are provided with a lower edge rail to keep the partition aligned with the doorway and in a stretched condition. These flexible partitions are typically comprised of a high strength plastic material such as polyvinyl chloride (PVC) and may be displaced from the open to the closed position, or visa versa, in just a few seconds. These types of partitions are generally limited in length and height by the weight of the partition itself. Counterbalancing arrangements are frequently provided to compensate for the weight of the partition, particularly when extended. Even the use of counterweight systems does not avoid the requirement to use increasingly larger electric motors and more complex support structures to accommodate large roll-up partitions. In addition, the weight of these overhead structures requires the spaced positioning of support members along the length of the overhead rotating tube. Splices are incorporated in the roll-up partition to accommodate these spaced support members along the length of the tube resulting in a partition with spaced gaps along its width. These gaps or splices limit the extent to which the partition can isolate the spaces on opposed sides of the partition from one another.
The present invention addresses the aforementioned limitations of the prior art by providing a roll-up door, curtain or partition which is of simplified construction, capable of high speed operation, can be very large in height and width, and is highly reliable and easily installed.